Wikipedia
"Evicted!" is the twelfth episode of the first season of the American animated television series Adventure Time. The episode was written and storyboarded by Bert Youn and Sean Jimenez, from a story by Adam Muto. It originally aired on Cartoon Network on March 18, 2010 as a preview for the series; it later officially aired on May 17, 2010. The episode guest stars Erik Estrada as King Worm. The episode marks the first appearance of Marceline the Vampire Queen (voiced by Olivia Olson), who would go on to play a larger role in the series as a friend and companion to Finn and Jake.
The series follows the adventures of Finn (voiced by Jeremy Shada), a human boy, and his best friend and adoptive brother Jake (voiced by John DiMaggio), a dog with magical powers to change shape and grow and shrink at will. In this episode, Finn and Jake search the land of Ooo for a new home after Marceline claims the duo's treehouse as her own. Finn and Jake search all of Ooo for a new home, before settling temporarily in a cave. After a final confrontation, Marceline relents and gives Finn and Jake their house back because she finds them entertaining.
The character of Marceline was present in the series' pitch bible, but she had not yet appeared in an episode prior to "Evicted!". Olson was cast as the character after she initially read for the part of Princess Bubblegum; she was later pleased with her casting, praising Marceline's varied design. "Evicted!" also features the first song that was produced for the series: "The House Hunting Song". "Evicted!" was watched by 1.88 million people and received largely positive critical attention, with Cam Shea of IGN naming the episode the fourth best episode of Adventure Times first season, and Oliver Sava of The A.V. Club noting that the episode is an example of the emotional complexity of the series. "Evicted!" also drastically increased Marceline's popularity with fans of the series.